1. Field of the Invention
The present invention relates to a safety device for fluid transfer systems and, more particularly, to a safety device for eliminating vacuum pressure in the system in response to an obstruction of one or more open intake lines, thereby removing a suction force at the open ends of intake lines in the system.
2. Description of the Related Art
Drowning is the second leading cause of unintentional injury related deaths to children 14 years old and younger. Most drownings occur in swimming pools and hot tubs, and in many incidents (involving both adults and children) the main culprit is the water circulation system. In a typical pool, the circulation system includes a main drain suction intake line and at least one skimmer suction intake line, both of which feed into a main intake line that leads to a pump. A return line directs water flow back into the pool.
Most people do not feel threatened by a pool""s circulation system, including the main drain intake on the bottom of the pool, and the skimmer boxes along the side of the pool. However, if a person comes into contact with any of the suction intake lines of the circulation system (at either the main drain or skimmer intakes) causing the suction intake to be covered or obstructed, the immense suction of the pump forms an instant seal between the open end of the suction intake line and the person""s skin or clothing. This may result if a person places their hand over the open end of the suction intake line or, as often happens with children, a person sits down on the suction intake. In either case, the force needed to pull them free often exceeds 800 pounds. Moreover, the injuries which are inflicted in a matter of a few seconds are horrific, usually permanent and sometimes fatal. If a person, especially a child, is sucked onto the main drain suction intake on the bottom of the pool, they usually drown.
The only way to free a person sucked onto the intake of a circulation system of this type, without causing severe injury or dismemberment, is to eliminate the vacuum (i.e. negative pressure) in the intake between the entrapped person and the pump, to thereby remove the intense suction force at the open end of the intake line. It is helpful to disable the source of the suction by interrupting power to the pump. However, even if the pump is shut down, a vacuum can remain in the intake side of the system between the pump and the obstructed end of the suction intake line. Sometimes, a victim could still be freed with some assistance, although serious injury or death may result. Ideally, if the vacuum in the intake line can be quickly eliminated after a victim becomes stuck to the intake, the victim will be freed with little or no assistance and without injury.
In the most instances wherein a victim becomes stuck to an intake of a circulation system, typically in a swimming pool or hot tub, rescuers fail to realize the need to immediately shut off the pump. Instead, in a panic, people tend to go the victim and attempt prying them free. In the rare instance this is successful, the injuries are often severe and permanent. Of course, there are also instances wherein there are no other people present to come to the victim""s rescue. These situations are almost always fatal.
The imminent danger presented by fluid circulation systems of the type commonly found in swimming pools, hot tubs, and the like has been longstanding in the art. Little, if any attention has been given to providing a satisfactory solution to this deadly problem that exists in every swimming pool, hot tub, as well as all other fluid circulation systems wherein a fluid is drawn from a reservoir through one or more suction intakes by a pump. Accordingly, there has been and there remains an urgent need to provide an effective means of preventing death and injury to those otherwise unfortunate victims who become unexpectedly attached (i.e., entrapped) by suction to the intake of a fluid circulation system.
The present invention is directed to a device for use in a fluid transfer. and/or circulation system of the type including at least one pump which draws water from a reservoir through one or more intake lines each extending from an open end at the reservoir to an intake of the pump. The primary purpose of the invention is to save lives and property by alleviating the intense vacuum that builds when one or more of the suction intake ports of a pump assisted fluid circulation system becomes obstructed. The safety device includes means for sensing one or more operating conditions in the fluid transfer/circulation system (e.g., negative pressure levels, positive pressure levels, water flow rate, pump voltage and/or amperage) and means for analyzing the sensed operating conditions. When the pump is operating, the safety device continually analyzes the operating conditions of the system. If the device detects a deviation of the operating conditions outside of a normal operational range, the vacuum pressure relief means are actuated in order to eliminate negative pressure in the system, thereby removing suction at the open ends of the intake lines. The device also disables the pump, shutting it off, upon detecting the abnormal operation condition(s). In the event there is an absence of fluid movement when the pump is operating (e.g., broken pipes, reservoir dry, etc.), the device triggers the vacuum pressure relief means and disables the pump, thereby preventing damage to the system. Warning devices, including audible and visible alarms, may be provided to indicate that operation of the fluid transfer system has been interrupted. This is especially useful to alert users to the possible occurrence of an obstruction of the intake lines by a person or object and the need to inspect and reset the device prior to reactivating the fluid transfer system. Other options can also be integrated with the device, including remote audible alarms, visual indicators, a remote panic switch, and the like.
With the foregoing in mind, it is a primary object of the present invention to provide a safety device for use in a fluid transfer/circulation system, wherein the device is structured to eliminate negative pressure in the system upon detecting a negative pressure level being outside of a selected operational range, thereby removing suction at the open ends of the intake lines.
It is a further object of the present invention to provide a safety device which is particularly useful in the fluid circulation systems of swimming pools, hot tubs and the like for preventing death and injury to persons or animals which become attached (i.e., entrapped) by suction to the intake openings of the system.
It is still a further object of the present invention to provide a safe, reliable and relatively inexpensive safety device for easy installation to existing fluid transfer/circulation systems and which automatically adjusts to any system, each time the fluid begins to flow, thereby establishing a normal operating range of conditions for each system, and wherein the device is structured to eliminate negative pressure in the system upon detecting an operating condition being outside (high or low) of the normal operating range, thereby removing suction at the open ends of the intake lines.
It is still a further object of the present invention to provide a reliable, relatively inexpensive safety device for use in a fluid transfer/circulation system of the type including at least one pump which draws water from a reservoir through one or more intake lines, and wherein the device is structured to deactivate the pump(s) and to further eliminate negative pressure in the system upon detecting one or more operating conditions of the system being outside of a predetermined range.
It is still a further object of the present invention to provide a safety device, as described above, further including warning devices such as, but not limited to, audible and visible alarms, to indicate that the safety device has been triggered to eliminate negative pressure in the intake lines of a fluid transfer system.
It is still a further object of the present invention to provide a safety device, as described above, which is contained in a totally sealed, compact unit for convenient, easy installation in-line with any fluid transfer/circulation system.
These and other objects and advantages of the present invention are more readily apparent with reference to the following detailed description taken in conjunction with the accompanying drawings.